Lifting-jack.



W. DANNENBERG.

LIFTING JACK. APPLICATION men APR@ 24, 1914.

Patented Mal'. 28, 1916.

2 SHEETS-SHEET l.

THE COLUMBIA PLANUGRAPH .60., WASHINGTON. u. L.,

w. DANNENBERG.

LIFHNG JACK.

APPLICATION FILED APR. 24. 1914.

2 SHEETS-SHEET 2.

Y HTW THE COLUMBIA PMNOGRAPH C0.. WASHINGTON, D. c.

Patented Mar. 28, 1916.

'Uni

Se n

rica.

LIFTINGr-J'ACK.

Application led Apr124, 1914.

view the invention consists in the combination and arrangement of parts to be hereinafter fully described in the following specification, pointed out in the claim and illustrated in the accompanying drawings which form a part of said specication and in which- Figure 1 is front elevation of my improved lifting jack. Fig. 2 is a section on line 2 2 of Fig. 1 with part of the tackle in section. Fig. 3 is a section taken on line 3 3 of Fig. 1. Fig. l is a section taken on line H of Fig. 5. Fig. V5 is a section taken on line 5-5 of F-ig. 1.

Like reference characters indicate corresponding parts throughout the several views.

The reference numeral 1 indicates the base of the jack provided with feet 2 and to the base a block 3 is bolted as at 4 which block and base, respectively, are apertured and recessed to receive the foot 5 of the screw 6 which is turned by a handle 7 litting holes in the head 8.

Copies of this patent may be obtained for Specification of Letters Patent.

Patented Mar. 28, 1916.

Serial No. 834,166.

9 is the tackle formed with prongs 10, 10 through which clamps 11, 11 project that engage the work to be raised and said tackle l is recessed as at 12 to form a clearance for the tongs 13 which are adapted to grip the screws 6 to effect movement of the tackle through operation of the said screw.

Operation: The clamps 11, 11 are adjusted about the work to be raised and rotation of the screw will raise the tackle and work. When the tackle has been raised into proximity with the head 3 said tackle may be lowered by disengaging the tongs from the screw when the tackle may be permitted to move to the base block 3 and a new purchase upon the work obtained. This arrangement avoids the necessity of reversing the screw to lower the tackle.

What is claimed is In a lifting jack, the combination with a base provided with a screw and means for rotating the same, of a recessed tackle, prongs formed integral with said tackle, oppositely disposed manually operable clamps carried by said prongs and tongs disposed in the recessed portion of said tackle for releasable engagement with said screw.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two subscribing witnesses.

WILLIAM DANNENBERG.

Witnesses:

EMIL NELVING, A. K. ANDERSON.

live cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

